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Climatic conditions are one of the most important factors affecting Camellia oleifera yield. A Camellia productive climate index system was established. Based on yield data of ordinary Camellia in Hunan Province, also with the daily meteorological observation data from the nearby meteorological stations (2006-2016), 33 climatic indicators involving 7 phenological periods were filtered from 1128 seared climatic indicators by correlation analysis, principal component analysis, yield trend analysis, numerical simulation, kernel density estimation and frequency integration of importance levels of climatic indicators. Results showed that the most important factors were climatic conditions at flowering, followed by those at the first fruit expansion, at the peak of oil conversion and accumulation, at the fruit ripening, at the spring budding, at the peak fruit expansion, and at the flower bud ripening. The spatial hierarchical structure and spatial correlation analysis among 33 key climate indicators were carried out. The indicators included duration with daily minimum temperature ≤ 0 at flowering, duration with precipitation at the first fruit expansion period, daily difference of average temperature at the key period of peak fruit expansion, and duration with high temperature at the peak of oil conversion and accumulation. They were selected to be representative and independent, and coupled with yield to establish the climatic zoning index of Camellia abundance. Based on the 500 m x 500 m meteorological grid data of Hunan Province from 1991-2020, the grid point zoning index was counted to obtain the climatic zoning of Camellia. Results showed that the climatic conditions of 90% Hunan were in favour of Camellia production. The most suitable climatic zones were mainly located in the hilly areas below 800 m in elevation, which was consistent with the spatial distribution of average yield in counties with Camellia area above 666.7 hm² in Hunan Province from 2017 to 2020. It was found that the main climatic conditions affecting yield in Hunan were not annual scale climatic conditions, but those at key phenological periods, from spring (budding) period of the last year. Each phenological period had its own specific conditions. [ABSTRACT FROM AUTHOR]